The invention relates, in general to coke ovens, and more particularly to an improved coke oven door for closing and opening to an oven chamber, the door being of the type having a door body, a door stopper mounted to the body on a side thereof adjacent to the oven chamber and designed to extend into the oven chamber, the coke oven having a door frame with a sealing surface bordering the opening, at least one planar sealing diaphragm secured to the door body between the door body and the door stopper, the diaphragm having sealing blades extended, along its periphery, inwardly against the sealing surface of the door frame, the sealing blades being mounted to the diaphragm about the outer peripheral area thereof, and spring means for urging the sealing blades against the door frame in order to seal the opening.
West German Utility Model No. 79 14 228 (U.S. Pat. No. 4,293,389)discloses a non-angled sealing diaphragm to which a sealing blade holder for a separate, exchangeable (reversible) sealing blade is welded in a gas-tight manner.
In addition to the foregoing diaphragm sealing technique, by means of a sealing blade, many attempts have been made and designs provided to improve tightness by means of an additional seal, to meet the increased requirements for environmental protection. West German Pat. No. 25 32 097 (U.S. Pat. No. 4,124,451) includes so-called antechamber seals having relatively large antechambers and an additional door frame sealing surface.
Further, West German Offenlegungsschrift No. 26 58 196 (U.S. Pat. No. 4,016,045) discloses a double seal for a coke oven door. The seal comprises a circumferentially extending elastically mounted sealing strip having two mutually parallel legs which come to apply against the chamber frame and enclose a hollow space. This sealing strip, however, is screwed only to the circumference of the door body, not to a throughgoing sealing diaphragm. Also, the two sealing legs are rigidly connected to each other and urged into contact by a single, common spring. If dirt or solid tar deposits behind one of these legs, the other leg automatically can no longer completely apply against the door frame and causes leaks.